The sender might not be aware of these underlying messages, but He Kao can interpret them.
Especially intriguing is that Senior Lin Qingshuang sent another annotated technique. She had previously annotated the Observation Secret Manual for He Kao, focusing mainly on pre-entry content.
This time, the annotation could no longer be called an annotation; it's more like an addition and revision, mainly targeting the content on the second and third pages.
If He Kao hadn't realized the Nihility View technique behind the portal, and the subsequent Insect Concealment Skill, but continued cultivating the set of "Hidden Moth Temple" he organized, then at this stage, he should be working on the subsequent techniques from this annotation.
Originally, Lin Qingshuang told him the later content couldn't be cultivated nor should it be.
